Depends on what you mean by "observer", but I'd guess you want "watchers". In the "people" area of an issue, there is a "watchers" list - clicking on that will take you to a screen where you can add people to that list (or remove them from it)
You will need to make sure you have "manage watchers" permission in the project.
I’m a designer on the Jira team. For a long time, I’ve fielded questions from other designers about how they should be using Jira Software with their design team. I’ve also heard feedback from other ...
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